Risperidone
Risperidone is listed as Risperdal, the brand-name tablet from Janssen Pharmaceuticals, in four strengths from 1 mg to 4 mg. This Mental Health medicine treats Schizophrenia, Bipolar I Disorder and irritability linked to autism.
Key points
- Second-generation antipsychotic: Risperidone was first approved in 1993 and carries a lower likelihood of causing movement side effects than older antipsychotics.
- Boxed warning: Older adults with dementia face an increased risk of death and stroke when treated with antipsychotics such as risperidone.
- Risperidone may raise blood sugar even in people without diabetes, and untreated high blood sugar can lead to ketoacidosis.
How does Risperidone work?
Risperidone changes the activity of certain natural substances in the brain. It blocks serotonin receptors and, to a lesser degree, dopamine receptors, which rebalances the chemical signals behind hallucinations, disorganised thinking and mood swings.
The drug also affects how serotonin and norepinephrine are recycled, which may explain its antidepressant effects. Unlike older antipsychotics, risperidone does not block acetylcholine receptors, a feature that may benefit certain populations. Its active metabolite, 9-hydroxy-risperidone, works alongside the parent compound, so the clinical effect reflects both.